Rock may contain hydrocarbons, such as oil or gas. Criteria used to estimate the existence and amount of hydrocarbons in rock include, for example, the types of chemical elements or minerals in the rock and the quantities of those chemical elements and minerals in the rock. To determine the existence and amount of organic material, such as hydrocarbons or kerogen, in rock, imaging techniques may be used to capture images of the rock. The resulting images can be analyzed to identify the existence, and amounts, of organic material in the rock.